Effect of lactoferrin feeding on the host antifungal response in guinea-pigs infected or immunised with Trichophyton mentagrophytes

Abstract

Earlier studies revealed that oral administration of lactoferrin (LF), a multi-functional milk protein, facilitated curing of dermatophytosis in guinea-pigs and man by an unknown mechanism. The present study aimed to assess the effect of feeding bovine LF on the host antifungal defence systems in guinea-pigs infected or immunised with Trichophyton mentagrophytes, a dermatophytosis-causing fungus. The unbound ironbinding capacity (UIBC) of the plasma of individual animals varied, and plasma with higher UIBC inhibited growth of T. mentagrophytes in vitro. However, LF administration did not enhance plasma UIBC or the anti-T. mentagrophytes activity of plasma in infected or uninfected animals. Phagocytic activity and reactive oxygen (RO) production of blood neutrophil polymorphonuclear leucocytes (PMNLs) were estimated by flow cytometry. LF administration caused no significant effects on phagocytic activity or RO production of neutrophil PMNLs in infected or uninfected animals. The functions of mononuclear cells (MNC) from the spleen were investigated in guinea-pigs immunised with heat-killed T. mentagrophytes conidia. The MNC were cultured with concanavalin A or inactivated T. mentagrophytes. In the bromo-deoxyuridine incorporation assay, the stimulation index was higher for MNC derived from LF-treated animals than for those from control animals. The culture supernates of MNC enhanced the ability of macrophages to kill T. mentagrophytes conidia. Furthermore, stronger augmentation was observed with the culture supernate from LF-treated animals than with that from control animals. In conclusion, LF feeding may potentiate the host antifungal defence systems by modulating MNC function rather than plasma antifungal activity or peripheral blood neutrophil PMNL activity.

Effect of orally administered bovine lactoferrin on the immune response in the oral candidiasis murine model

“…Further examination is necessary of the influence of LF feeding on immunological events in the oral tissue using this model. In the past few years, several immunomodulatory effects of ingested LF in animals have been reported (Sekine et al, 1997;Wakabayashi et al, 2002). Very recently, we showed that LF feeding augmented macrophage activity at the local site where inactivated Candida was injected as a priming agent (Wakabayashi et al, 2003).…”

Efficacy and tolerability of oral lactoferrin supplementation in mild to moderate acne vulgaris: an exploratory study

“…However, it seems more likely that ingested lactoferrin indirectly promotes systemic immune responses 26,28 , because oral lactoferrin is subject to pepsin proteolysis and may not reach the systemic circulation to a large extent 29 . The host defense against microbial infection may be enhanced by lactoferrin via a network of intestinal mucosal and systemic immunity 14,[29][30][31] . In addition, it has been reported that oral intake of bovine lactoferrin enhanced the production of interleukin-18 in intestinal epithelial cells and of interferon-g in the lamina propria, and increased the numbers of CD4 þ , CD8 þ , and natural killer cells in the intestinal mucosa of both tumor-bearing mice and normal mice 29 .…”

Lactoferrin

“…Enhancement of macrophage activities was detected by nitric oxide production, inhibition of Candida growth, and IFN-g and IL-12 levels in the peritoneal cavity [54]. In guinea pigs that were immunized with inactivated Trichophyton mentagrophytes, bLf feeding enhanced splenocyte secretion of a humoral factor that promotes fungicidal activity of macrophages [55]. Recently, clinical trials were conducted that explored immuno-modulatory effects of bLf.…”